West Ham manager Sam Allardyce believes Arsenal only have themselves to blame for their frustrating season.

The Gunners have found life tough this term and recent back-to-back Premier League defeats against Manchester City and Chelsea leave them seven points off fourth spot, while they are a mammoth 22 points off league leaders Manchester United.

And Allardyce, who will be looking for a first away win at Arsenal when he takes his West Ham side to the Emirates on Wednesday night, feels his opponents have landed themselves in this position by selling off their best players, such as Robin van Persie, without bringing in suitable replacements.

"It's not surprising because I don't know where you go and buy a player of Van Persie's quality unless you're going to pay more than £24 million," Allardyce said in The Sun. "Everybody says it's great business in terms of his age but it's not really great business for Arsene Wenger when he can't replace the goals that he's lost.

"When you sell your best players, which is not normally expected of Arsenal, then it is difficult to replace them. There is no doubt the players who have come in are very good but are they better than the ones they have sold?

"It's a big ask, even for Arsene with his huge recruitment policy, to replace those players immediately. They have suffered with their level of results. The football is still very good but when you lose that many goals - particularly from Van Persie - and miss more chances than they did before, they won't get as good results.

"I'm sure Arsene is frustrated because he's been the best manager Arsenal have ever had. When you build the club and then cannot sustain that, it becomes very frustrating for any manager. They are still one of the top sides but they are just going through a period of transition with the amount of players they have lost.

"They played Chelsea on Sunday and we played 24 hours earlier on Saturday, which gives us a slight advantage physically because they've had less time to recover. We also hope the disappointment of their 2-1 defeat against Chelsea means there might be a little lack of confidence. If that's the case then we might have a chance of getting a result. If Arsenal are on top form, then Arsenal will beat us, no matter how well we play."

Press Pass Extra: Gunners seek winning formula

Allardyce and Wenger have a history of feuds running back to the former's Bolton days, something that the Hammers boss admits he has taken some pleasure from.

"We had some tussles. Whenever we beat Arsenal, if we weren't labelled 'long ball' then it would be 'physical'," Allardyce said.

"It was frustrating but it used to make me really enjoy the fact we beat an Arsenal side which included players like Thierry Henry and Patrick Vieira. It was about finding a chink in their armour and exposing it.

"When you do that to top teams and beat them then their manager is not going to be very happy."

Key battle: Jack Wilshere's winner against Swansea last week confirmed that the midfielder is back to his best. In Mark Noble he will come up against a player whose commitment to the tackle is second to none.

Player to watch: With Mikel Arteta still unavailable and Abou Diaby a doubt, Aaron Ramsey could be handed a rare start in midfield. The Wales international has been linked with a loan move away from Emirates Stadium in pursuit of more regular football, but a big performance against the Hammers would give him the chance to stake his claim for a regular first-team spot.

Talking point: West Ham boss Sam Allardyce says Arsenal only have themselves to blame for their frustrating season after failing to bring in suitable replacements having sold their best players. Wenger has stressed his intention to bring in new players in January, but will he stump up the cash?

Bet of the day: Alex Oxlade-Chamberlain has just one Premier League goal to his name this season. We reckon he must be due another one - back him to score anytime at odds of 17/2 with bet 365.